- Crohn's Disease patients with previous failure with TNF (Tumor Necrosis Factor) antagonist agents and unacceptable side-effects from steroids, and/or immunosuppressive agents (i.e., azathioprine, 6-mercaptopurine, or methotrexate). In France, Vedolizumab has to be prescribed only in patients in failure or intolerant to anti-TNF.